Patent GB-932727-A (GB)
Title: Improvements in or relating to methods of and means for shearing animals more especially sheep
IPC: B26B19/24
Filed: 1962-02-27
Abstract: 932,727. Sheep &c. shearing apparatus. W. R. C. GEARY. Feb. 27, 1962 [March 1, 1961; Dec. 14, 1961], No. 7704/62. Class 131. Shearing apparatus for sheep and other animals comprises elongate severing means adapted to conform to the body contours of an animal when arranged substantially lengthwise thereon and means operable to move the severing means at least partly around and substantially in contact with the body of the animal. As shown in Fig. 1, a conveyer comprises a cable 10 passing around pulleys 12 and having suspended therefrom spaced carriage bars 18 each provided with means for suspending an animal by its legs so that it hangs in an inverted condition. The conveyer serves to move the animals in succession and preferably tail first to a shearing station. Shearing apparatus at the shearing station comprises a chain-like assembly of cutter units 20 supported by a frame 22, the arms 22a of which are pivotally connected to a fixed bracket structure 24 by coaxial pivot pins 26, the frame 22 being raised and lowered by means of an air cylinder 28. The free end of one of the arms 22a also carries a pivoted headrest and shield 29. Rotatably mounted in the free end of each arm 22a is a spindle 30 the inner end of which is fixed to a tubular arm 32. The arms 32 slidably support the ends of a bar 34 so that the latter is movable towards and from the axis 30 by means of air cylinders 40, Fig. 3, the inner and outer limits of movement of the bar 34 being determined by stops 38, 39 respectively. The outer end of each spindle 30 is fitted with a pinion 43 meshing with a rack 42 connected to the plunger rod 44 of an air cylinder 45 secured to an arm 22 so that when the racks are operated, the arms 32 are turned in either direction. The bar 34 carries a plurality of air cylinders 48 having tubular plungers 49 which comprise spring-influenced plugs 50. Each cylinder 48 is mounted on the bar 34 by means of a pivot pin 56. Each plug 50 is formed with lugs which are pivotally connected to the rear end of an arm 60 having its front end extending between and hingedly connected to an adjacent pair of cutter units 20. Each cutter unit comprises a fixed comb 62 and a toothed cutter plate 63 (not shown) reciprocable sidewise by means of an air operated driving motor. Each cutter unit is provided with an angularly-adjustable roller 68 which may be power driven to assist in stretching the skin of the animal. Instead of driving the rollers 68, one or more power-driven skinstretching rollers may be arranged behind the cutter units and supported independently thereof by the arms 32. In use, the pivoted frame 22 normally occupies its lowermost position (Fig. 9) with the bar 34 in its outermost position and the plungers 49 of the cylinders 48 fully retracted by their springs 52. When each animal is moved to and stopped at the shearing station, air is supplied to the cylinder 28 to raise the frame 22 to the operative position. At this time, the suspended animal is between the arms 32. As the frame is being moved upwardly, the headrest 29 engages and cradles the head of the animal and moves it between or in close proximity to its forelegs. After the frame 22 has been fully raised, compressed air is supplied to the cylinders 40 to move the bar 34 inwardly to its full extent so that the cutter units 20 are moved towards the adjacent side of the animal though not into contact therewith. Low pressure air is then supplied to the outer end of each of the cylinders 48 to move the assembly of cutter units into contact with the body of the animal. At this stage, compressed air is supplied to the driving motors of the individual cutter units so as to reciprocate the cutter plates thereof across the respective combs after which air is supplied to the cylinders 45 so that the racks 42 are actuated to turn the arms 32 in unison and in the clockwise direction in Fig. 10, whereby the cutter units move downwards over the adjacent side of the animal, then below the back thereof and finally upwardly as shown in Fig. 11, and during this movement the cutter units move inwards and outwards as required to conform to the body curvature of the animal. The fleece is thus severed during a single sweep of the assembly of cutter units. When the arms 32 complete their clockwise movement, the cylinders 48 are connected to exhaust so that the springs 52 withdraw the cutter units from the animal after which they are fully withdrawn by moving the bar 34 to its outermost position. The arms 32 are then turned in unison and in the opposite direction whereby they are returned to the start position (Fig. 10) and finally they are lowered to the original position by means of the frame 22 to enable the conveyer to move the shorn animal onwards and simultaneously to move a fresh animal to the shearing station.